After its complete destruction in the Middle Ages, even its location was forgotten. Exactly where the mysterious Schwanenburg in Münsterland once was has now been uncovered by archaeologists through large-scale geomagnetic investigations of the subsoil. The findings near Rheine in the district of Steinfurt make it clear that it was an impressive castle complex with ramparts that lay on a natural island between the oxbow lakes of the Ems River.
It was probably built sometime in the 13th century – historical documents tell of a castle in the Münsterland, the location of which, however, was only described imprecisely: it is said to have been near Rheine-Elte in the floodplain of the Ems. It was therefore a so-called lowland castle, which was probably surrounded by water. The complex was called Schwanenburg because it belonged to the noble lords of Steinfurt, whose coat of arms was adorned with the elegant water bird. There are also historical records of the end of the fortifications: it was destroyed in 1343 as part of a feud between the Steinfurt residents, Bishop Ludwig of Hesse and the Counts of Mark from Münster. It was not rebuilt afterwards and apparently served extensively as a source of building material for the local population.
Archeology without spade and brush
“The exact location was then gradually forgotten,” says Joris Coolen from the Regional Association of Westphalia-Lippe (LWL). As he reports, efforts have been made for years to find the former location of the castle. But so far there have been no clear results. Local historian Andreas Brinker from Rheine then provided the impetus for the current investigation: In the digital terrain model of the state of North Rhine-Westphalia, he discovered conspicuous structures in an area where the long-sought castle might have once stood. Brinker then presented his information to the LWL experts.
They then decided to take a closer look at the area using modern measuring equipment. Although it had already been examined in 2002 by the Institute for Geophysics at the University of Münster, the results were unclear. “With today’s technology, we work much faster and can therefore examine large areas in a short time,” explains Coolen. “Especially in this case it was shown again that the large areas make the difference. We were only able to identify the magnetic disturbance as a medieval moat because we also examined a larger area around the suspected castle complex.” This means that the archaeologists have now clearly localized the former location of the Schwanenburg for the first time. According to the LWL, their tracks underground are south of the B475 near the Willer and Strotmann farms.
Impressive complex with river view
The results of the investigation also enabled conclusions to be drawn about the dimensions of the facility: “Based on the magnetic data, the diameter including the trenches can be estimated at around 100 meters. The inner surface has a diameter of around 60 meters. This means that the Schwanenburg was probably one of the larger lowland castles in the Münsterland,” says Coolen, classifying the findings. It was apparently framed by two backwaters of the Ems, giving the castle a natural island location on the northern edge of the Ems lowlands. It was probably easy to reach from the north via dry areas and paths. “Parts of the old arms were then expanded into ponds in modern times, so that areas of the former moat system are likely to have been destroyed,” says LWL archaeologist Ingo Pfeffer. Today, nothing conspicuous can be seen at the location – almost symbolically, however, swans occasionally circle on the ponds.
Due to the current findings, the discussion about the location of the medieval complex has ended – but the Schwanenburg remains mysterious. Because based on the measurement data, hardly any statements can be made about the appearance of the building. “You would have to do excavations for that,” says Pfeffer. But that will obviously not exist for the time being: “That would certainly be exciting, but an excavation costs a lot of time and money, and the castle complex is also located in a nature reserve. That’s why no excavations are planned for the time being,” says the archaeologist.